Great Basin National Park

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Lehman Caves (a single cavern despite the name) extends a quarter-mile into the limestone and low-grade marble that flanks the base of the Snake Range. Discovered about 1885 by Absalom Lehman, a rancher and miner, this cavern is one of the most richly decorated caves in the country, a small but sparkling gem.

What we see today began millions of years ago. The climate then was much wetter than it is now. Rain water, turned slightly acidic by seeping past surface vegetation and humus, found its way into hairline cracks deep in the native limestone. Trickling downward, the water dissolved the stone, enlarging the cracks, eventually reaching the water table. There it collected in sufficient quantity to create whole rooms. At one time, an underground stream flowed here, leaving behind tell tale ripple marks.

Eventually the climate turned drier, water drained from the cave, leaving smooth walls and hollow rooms. Then came the second stage of cave development. Small amounts of water still percolated down from the surface. But now, instead of enlarging the cavern, the mineral-rich fluid began filling it once again. Drop by drop, over centuries, seemingly insignificant trickles worked wonders in stone. The result is a rich display of cave formations, or as scientists call them, speleothems. Lehman Caves contains familiar structures such as stalactites, stalagmites, columns, draperies, and flow stone, along with some interesting and delicate rarities.

Lehman Caves is most famous for the rare and mysterious structures called shields. Shields consist of two roughly circular halves, almost like flattened clam shells. How they are formed remains a subject of controversyanother of the pleasant mysteries to be found in the underground world.

History

The discovery of Lehman Caves is credited to Absalom Lehman, a local rancher. He made his discovery in the spring of 1885. Lehman's curiosity and experience as a miner prompted his investigation of the mysterious opening near his ranch. Although Native Americans knew of the cave, Lehman was the first person to explore the underground world. What Lehman found was astonishing, for Lehman Caves is rare among caves for it is profusely decorated with a great variety of calcite formations.

Lehman Caves with its unique and spectacular features was first set aside as a National Monument under the United States Forest Service in 1922; and has been protected as part of the National Park Service since 1933 and as a National Park since 1986.

Formation of the Cave

Lehman Caves is a prime example of a limestone solution cavern. Its beginning can be traced back 550 to 600 million years ago when most of what is now Nevada and western Utah was covered by a warm, shallow sea. Over the next 400 million years, sea creatures lived and died, piling oozy layer upon oozy layer of calcium carbonate-rich sediment on the ocean floor. These oozy sediments gradually solidified into rock known as limestone.

About 70 million years ago these limestone layers became exposed to the elements. For many years rain and melting snow soaked through the soil and combined with carbon dioxide gas from decaying plants and animals to form a weak solution of carbonic acid. This acidic solution percolated downward through tiny cracks until it reached the water table. The limestone around these water-filled cracks slowly dissolved. Eventually these cracks grew into the rooms and passageways that make up Lehman Caves. Over time the water in these underground chambers drained away.

Seeping water continued to enter these passages and chambers. Every drop carried with it a small amount of dissolved limestone. When the solution was exposed to the air of the open chamber, the carbon dioxide gas escaped from the solution, and thus allowed calcite and other minerals to be deposited along the walls, ceilings and floors. These deposits created the beautiful and mysterious formations we know as speleothems. Even today these processes of growth continue to decorate the passages and rooms of the cave. Lehman Caves is decorated with fantastic examples of stalactites, stalagmites, columns, draperies, flowstone, helectites, and rare shield formations. Tours are available through this wondrous world.

Cave Walk Information

Three different cave walks are given: the 30-minute tour, 60-minute tour (0.4 miles round-trip), and 90-minute tour (0.54 miles round-trip), all on a hard surface trail with several sets of stairs. Tour size is limited to 25 people, no exceptions. Narrow passages and small rooms limit the number of people that can be safely led through the cave. The cave is a constant 50 degrees Fahrenheit (10 degrees Celsius). A light jacket, sweatshirt, or sweater may be required for your comfort. All tours may include a brief period where the ranger turns off the lights to demonstrate complete darkness.

Great Basin National Park has established an advanced ticket sales system. Tickets may be purchased up to one month in advance (see below for details) or on the day, although the latter option may lead to a wait as tours are scheduled and limited to 25 persons per tour.

Visitors may purchase advance tickets in person at the visitor center or by phone at (775) 234-7331 ext. 242. The Visitor Center's hours are 7:30am to 6:00pm during the summer, 8:30am to 5:00pm in winter. Advance tickets may be purchased between 8:30am and 5:00pm Pacific Standard Time. All advance tickets must be paid for at the time of purchase. Master Card and Visa are accepted for phone orders. Golden Age and Access Passports must be in hand at the time of ticket purchase. All advance ticket sales are final so please plan your trip accordingly. A maximum of 12 spaces per walk are available for advance sale.

Published: 29 Apr 2002 | Last Updated: 15 Sep 2010 Details mentioned in this article were accurate at the time of publication